Physical barriers are commonly used to seal orifices in certain objects, such as panel members in motor vehicles, buildings, household appliances, etc. These barriers normally are used to prevent physical materials, fluids, and gases, such as environmental contaminants, fumes, dirt, dust, moisture, water, etc., from passing through the orifice. For example, an automotive panel, such as a door panel, typically has several orifices in the sheet metal, which are created for various reasons during manufacturing. Further, various structural components of automobile bodies have a variety of orifices, hollow posts, cavities, passages and openings that can allow contaminants into the passenger compartment. These holes, orifices, and cavities are typically barricaded with duct tape, butyl-based plastic patches, and sealing plugs made from foam, rubber, or some other material. Another known physical barrier for cavities involves introducing a foam product or a fiberglass matting to fill in the cavity.
Known barriers, however, are unsatisfactory for a variety of reasons. Sealing plugs, which were a step forward over other barriers, utilize snap-fit clips to hold the plug in place, i.e., in an orifice of a panel member. However, snap-fit clips on a sealing plug, without more, are insufficient because the clips cannot produce a contaminant-tight seal between the plug and the panel member. To overcome this, a sealer material, such as compressible rubber, adhesive, caulk or mastic, has been used in combination with a carrier to form the sealing plug. The sealer material may create a contaminant-tight seal between the carrier and the panel member.
With the introduction of the sealer material, however, new drawbacks arise. Often the sealer material needs to be activated in order to form a contaminant tight seal. Such activation may be in the form of mixing two components together or physical kneading of the material. This can be labor intensive, as well as placing a time limit on the installation process because the barrier must be placed in the orifice during the relatively limited active period of the sealer material. Furthermore, known sealer materials have not been able to protect against prolonged exposure to contaminants, but only against intermittent exposure to contaminants. This is a particular problem with respect to water.
Installation of known snap-fit barriers has also been problematic because installation of such barriers exactly in the center of the orifice has been difficult. Once the barrier is placed askew in the orifice, the presence of the sealer material prevents the barrier from centering itself. For the same reason, it is also difficult for the installer to center the barrier.
This skewed or off-center installation of the barrier creates two problems. First, it places unequal strain on the snap-fit clips that hold the barrier in place. This tends to lead to failure of one or more of the clips, which results in a leaky seal. To overcome this type of failure, stiffer snap-fit clips, which require more force to flex, are required. This in turn increases the force needed to install the barrier into the orifice to such a degree that a person cannot perform installation without mechanical assistance. Thus, force-multiplying tools or machines are required to install the barrier. The use of tools or machines to install these barriers increases the complexity and cost of the installation process beyond that which is economical.
Second, off-center installation increases the number of failed seals. Known sealer materials cannot compensate for off-center installation. Off-center installation can lead to gaps between the panel member and the carrier that are not filled by the sealer material. Thus, the size of the barrier must be closely matched to the size of the orifice to ensure that there are no gaps between the carrier and the panel member. Therefore, expensive precision manufacturing techniques are required in the formation of the orifice and the carrier to ensure that the barrier cannot be installed incorrectly, i.e., off-center.
Consequently, the inventor hereof has recognized a need for a physical barrier that overcomes one or more of these problems.